Boeing received an early Christmas present from the US Congress last week, as lawmakers granted an extension of the deadline for certifying the Max 7 and Max 10 versions of the B737 single aisle jetliner.

The exemption allows the plane maker to have the new variants certified under existing requirements.

The extension was one of several provisions included in the $1.7 trillion omnibus appropriations bill to fund the US government for the fiscal year 2023. The legislation was passed and sent to President Biden’s desk in a last-minute vote prior to the end of the current Congress.

Without Congressional action, the new variants would have been required to include redesigned crew alerting systems, and would have been treated as a new aircraft type, prompting a lengthy recertification process.

According to Boeing, the additional delay would have put the future of the Max 7 and 10 in doubt, and jeopardized $50 billion in orders for the new aircraft already on Boeing’s books, including Delta Air Lines’ order of 100 Max 10s announced in July.

In 2020, following two deadly accidents involving earlier versions of the B737 Max, Congress passed the Aircraft Certification, Safety and Accountability Act.

The law required all aircraft certified by the Federal Aviation Administration after Dec. 27, 2022, to have the updated crew alerting systems.

The crashes forced the entire fleet to be grounded for nearly two years while the aircraft underwent software updates and extensive crew retraining.

By the end of 2020, most international aviation authorities had recertified the current versions of the aircraft to return to the skies.

Boeing had expected the newer Max 7s and Max 10s to complete the certification process under the pre-2022 requirements. However, FAA approval has taken longer than expected.

The exemption written the spending bill allows the FAA to certify the Max 7 and Max 10 under current rules, but in addition, does require Boeing to retrofit the entire fleet of B737s with two fixes designed to improve its flight control system.

The requirement must be completed at Boeing’s expense within three years of the Max 10 certification.

The Max 10 is being already being flight tested with the updated system on board. Boeing expects the Max 7 to complete certification in the first few months of 2023, with the larger Max 10 likely to be certified by late 2023.

The extension caps a month of good news for Boeing, as earlier in December, the plane maker announced an agreement with United Airlines for 100 more B787 Dreamliners, the largest order for the wide-body jets in Boeing’s history.

United places largest ever Dreamliner order